If you have the URE installed, then this Rexx script can be used to delete a >2 KiB OS2.INI entry, which a.o. seems to refer to the temporary install directory of the URE (unverified):
/**/
CALL RxFuncAdd 'SysIni','RexxUtil','SysIni'
CALL SysIni 'USER','URE.Install','DELETE:'
EXIT